PROJECT SUMMARY/ABSTRACT The objective of this project is to conjugate a therapeutic antibody relevant to lymphoma to an optimized MYC G-quadruplex (G4)-stabilizing DNA interference (DNAi) for the treatment of MYC-overexpressing, aggressive, diffuse large B-cell and mantle cell lymphomas (DLBCL and MCL, respectively). This project will serve as a model for the further development of antibody conjugated DNAi targeting either other tumor cells or G4s in other key oncogenes, such as conjugation to trastuzumab for Her2+ breast cancer or with Bcl-2 targeting DNAi for other liquid tumors, respectively. Our central hypotheses are that 1) replacing the phosphodiester backbone of the DNAi with a morpholino, either alone or fused to a cell- or nuclear-penetrating peptide, will improve the intracellular stability and localization of the DNAi, 2) therapeutic antibodies can be conjugated to morpholinos with various linkers to create a plasma stable, yet cleavable in a lysosome, antibody-morpholino conjugate (AMC), and that 3) this conjugate will selectively delivery the DNAi to antigen-presenting lymphoma cells, but not other, antigen-null cells. Our objective and hypothesis are supported by literature describing the poor response of MYC-overexpressing DLBCL and MCL patients to the standard chemotherapy regimen, the value of downregulating MYC in aggressive NHL diseases via stabilization of the promoter G4, and the conjugation of siRNA/oligonucleotides to both CPP/NLS peptides and to antibodies. To achieve our objective and to test our central hypothesis, we will: 1) Optimize DNAi for nuclear penetration and cellular stability; 2) Establish chemistry for the conjugation of antibodies to DNAi; and 3) Demonstrate the intracellular penetration and functional activity of antibody:DNAi conjugates. Successful completion of the proposed studies will enable the selection of a pre-clinical candidate that will be evaluated for efficacy and safety in a standard model of aggressive NHL in combination studies with standard of care chemotherapy. This work will positively impact DLBCL and MCL cancer patients harboring dysregulated MYC, be applicable to other MYC-reliant cancers, including breast, prostate, and leukemia, and MYC-related non-oncogenic conditions, such as liver fibrosis and stent restenosis. Success of this application will establish a model for targeted delivery G4-targeting DNAi's targeting other additional high-value genes important in biomedicine and will serve as justification for future funding opportunities. In support of the program goals of REAP, these aims were specifically designed for student integration and learning within the School of Pharmacy and Pharmaceutical Sciences at Binghamton University to enable their research into molecular biology, medicinal chemistry, and therapeutic development.